In a terrific sequel to The Widower's Two-Step, which won the 1999 Edgar for Best Original Paperback, the third Tres Navarre mystery finds the academic-turned-PI reluctant to accept a chair in medieval studies at the University of Texas at San Antonio, a chair whose last two tenants have met with violent deaths. But when a bomb goes off in the dean's office nearly killing him and two others, he instantly accepts the assignment. Tres quickly finds out that the second victim's father, Jeremiah Brandon, a ruthless amusement-park ride manufacturer known as the ""King of the Carnivals,"" was also murdered years before. The prime suspect then was Jeremiah's former employee, gang member Zeta Sanchez, who believed that the predatory Jeremiah was sleeping with his wife, but Sanchez was never apprehended. Suddenly it is reported that, after years on the run (and in a Mexican jail), he has been spotted in the region. Tagging along with the San Antonio police, Tres finds himself in the middle of a violent shoot-out during which Sanchez is arrested; now he is also the number one suspect in the murder of Jeremiah's son. Not surprisingly, Sanchez vigorously protests his innocence. All this happens in just the first 40 pages of this fast-paced and highly entertaining novel, as Tres finds himself drawn into the complex vortex of the Brandon family's ugly past. With the help of beautiful yet tough homicide detective Ana DeLeon (a potential romantic interest) and other, less than savory, friends from the wrong side of the law, the wisecracking Tres untangles an intricate web of murderous family rivalries, missing persons and heroin traffic--all the while evoking with bright color the interplay of San Antonio's Latino and Anglo cultures and the joys of Tex-Mex cuisine. (Jan.)